[pbs-devel] applied: [PATCH] fix: use fragmented block size for space calculation

[Thomas Lamprecht]

Am 22/01/2024 um 15:23 schrieb Gabriel Goller:
> We currently calculate the size of a datastore using `statfs64`, which
> returns the number of blocks in the fs and the two block sizes:
> fragemented block size(f_frsize) and block size (f_bsize). To calculate
> eg the total space in a datastore we use total_blocks * f_bsize, which
> is not always correct.
> 
> `f_frsize` is the minimum unit of allocation on the filesystem (in
> bytes) and in 99% of the cases equal to `f_bsize`, but in some cases
> it differs. For example some filesystems allow smaller blocks for small
> files, in case f_frsize < f_bsize. In that case, f_frsize * total_blocks
> returns (mostly) the correct result (ceph also did some weird stuff, which is
> now being fixed though [0][1]). `statvfs` also documents this as the
> recommended way ('fsblkcnt_t f_blocks;   /* Size of fs in f_frsize units */')[2].
> 
> This patch aligns the the behavior with the libc utilities (also used by
> `df`) [3].
> 
> Motivation: [4] (Forum post)
> 
> [0]: https://tracker.ceph.com/issues/3793
> [1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=92a49fb0f79f3300e6e50ddf56238e70678e4202
> [2]: https://www.man7.org/linux/man-pages/man3/statvfs.3.html
> [3]: https://git.savannah.gnu.org/cgit/gnulib.git/tree/lib/fsusage.c#n147
> [4]: https://forum.proxmox.com/threads/pbs-3-1-2-wrong-datastore-information-sshfs.139875/#post-626959
> 
> Signed-off-by: Gabriel Goller <g.goller at proxmox.com>
> ---
>  proxmox-sys/src/fs/mod.rs | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
> 
>

applied, thanks!